Wearable Fixation Device for a Magnetically Controllable Therapeutic Agent Carrier: Application to Cartilage Repair

Recently, significant research efforts have been devoted toward the development of magnetically controllable drug delivery systems, however, drug fixation after targeting remains a challenge hindering long-term therapeutic efficacy. To overcome this issue, we present a wearable therapeutic fixation device for fixing magnetically controllable therapeutic agent carriers (MCTACs) at defect sites and its application to cartilage repair using stem cell therapeutics. The developed device comprises an array of permanent magnets based on the Halbach array principle and a wearable band capable of wrapping the target body. The design of the permanent magnet array, in terms of the number of magnets and array configuration, was determined through univariate search optimization and 3D simulation. The device was fabricated for a given rat model and yielded a strong magnetic flux density (exceeding 40 mT) in the region of interest that was capable of fixing the MCTAC at the desired defect site. Through in-vitro and in-vivo experiments, we successfully demonstrated that MCTACs, both a stem cell spheroid and a micro-scaffold for cartilage repair, could be immobilized at defect sites. This research is expected to advance precise drug delivery technology based on MCTACs, enabling subject-specific routine life therapeutics. Further studies involving the proposed wearable fixation device will be conducted considering prognostics under actual clinical settings.

Cohen Syndrome Patient iPSC-Derived Neurospheres and Forebrain-Like Glutamatergic Neurons Reveal Reduced Proliferation of Neural Progenitor Cells and Altered Expression of Synapse Genes

Cohen syndrome (CS), a rare autosomal recessive disorder, has been associated with genetic mutations in the VPS13B gene, which regulates vesicle-mediated protein sorting and transport. However, the cellular mechanism underlying CS pathogenesis in patient-derived human neurons remains unknown. We identified a novel compound heterozygous mutation, due to homozygous variation of biparental origin and heterozygous variation inherited from the father, in the VPS13B gene in a 20-month-old female patient. To understand the cellular pathogenic mechanisms, we generated induced pluripotent stem cells (iPSCs) from the fibroblasts of the CS patient. The iPSCs were differentiated into forebrain-like functional glutamatergic neurons or neurospheres. Functional annotation from transcriptomic analysis using CS iPSC-derived neurons revealed that synapse-related functions were enriched among the upregulated and downregulated genes in the CS neurons, whereas processes associated with neurodevelopment were enriched in the downregulated genes. The developing CS neurospheres were small in size compared to control neurospheres, likely due to the reduced proliferation of SOX2-positive neural stem cells. Moreover, the number of SV2B-positive puncta and spine-like structures was significantly reduced in the CS neurons, suggesting synaptic dysfunction. Taking these findings together, for the first time, we report a potential cellular pathogenic mechanism which reveals the alteration of neurodevelopment-related genes and the dysregulation of synaptic function in the human induced neurons differentiated from iPSCs and neurospheres of a CS patient.

Autophagy pathway upregulation in a human iPSC-derived neuronal model of Cohen syndrome with VPS13B missense mutations

Significant clinical symptoms of Cohen syndrome (CS), a rare autosomal recessive disorder, include intellectual disability, facial dysmorphism, postnatal microcephaly, retinal dystrophy, and intermittent neutropenia. CS has been associated with mutations in the VPS13B (vacuolar protein sorting 13 homolog B) gene, which regulates vesicle-mediated protein sorting and transport; however, the cellular mechanism underlying CS pathogenesis in patient-derived neurons remains uncertain. This report states that autophagic vacuoles accumulate in CS fibroblasts and the axonal terminals of CS patient-specific induced pluripotent stem cells (CS iPSC)-derived neurons; additionally, autophagic flux was significantly increased in CS-derived neurons compared to control neurons. VPS13B knockout HeLa cell lines generated using the CRISPR/Cas9 genome editing system showed significant upregulation of autophagic flux, indicating that VSP13B may be associated with autophagy in CS. Transcriptomic analysis focusing on the autophagy pathway revealed that genes associated with autophagosome organization were dysregulated in CS-derived neurons. ATG4C is a mammalian ATG4 paralog and a crucial regulatory component of the autophagosome biogenesis/recycling pathway. ATG4C was significantly upregulated in CS-derived neurons, indicating that autophagy is upregulated in CS neurons. The autophagy pathway in CS neurons may be associated with the pathophysiology exhibited in the neural network of CS patients.

The current state of patient access to new drugs in South Korea under the positive list system: evaluation of the changes since the new review pathways

Objective: This study aims to provide an up-to-date analysis of the current state of patient access to new drugs in South Korea, focusing on the effect of new review pathways for reimbursement. Methods: We analyzed patients' access to new drugs, listing rate and lead time until listing from marketing authorization. New pathways were defined as 'price negotiation waiver,' 'risk-sharing agreements,' and 'pharmacoeconomic evaluation exemption.' Results: The listing rate for drugs increased after the introduction of the new pathways (93.7% vs. 77.9%, p < 0.001). Before the new pathways, the median lead time for listing was 21.0 months (95% CI: 16.9-25.0), while afterward it was shortened to 10.9 months (95% CI: 10.2-11.7) (p < 0.001). Conclusion: Although it has strengthened national health insurance coverage by positively impacting the rate and lead time, the lead time for the oncology and orphan drugs is substantially longer as compared to other drugs. Expanding the eligibility criteria to include non-life-threatening but rare or intractable diseases, and resolving the system's operational issues are still necessary.

Enhancement of cortisol measurement sensitivity by laser illumination for AlGaN/GaN transistor biosensor

In this study, high electron mobility transistor (HEMT) device was used as an immuno biosensor to measure concentration of a stress hormone, cortisol, by using selective binding on cortisol monoclonal antibody (c-Mab). Also, the HEMT sensor was enhanced in its sensitivity through light illumination to generate photocurrent. The optical pumping could assist the biosensor to discriminate more detailed change, which could result in an increment of limit of detection (LOD) to 1.0 pM cortisol level. It was the lowest level of detection with semiconductor device-based cortisol biosensors and the enhancement of surface potential sensitivity was induced by laser light (532 nm). Output current amplificated by photocurrent was higher than dark original current at about 3.39% when gate voltage is applied with -3 V. Since the device could be applied to not only standard cortisol solution but also real human salivary sample, it is expected to apply for in vitro direct diagnosis of point-of-care test (POCT).

Identification of a novel Shank2 transcriptional variant in Shank2 knockout mouse model of autism spectrum disorder

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders that are highly heterogeneous in clinical symptoms as well as etiologies. Mutations in SHANK2 are associated with ASD and accordingly, Shank2 knockout mouse shows ASD-like behavioral phenotypes, including social deficits. Intriguingly, two lines of Shank2 knockout (KO) mouse generated by deleting different exons (exon 6-7 or exon 7) showed distinct cellular phenotypes. Previously, we compared gene expressions between Shank2 KOs lacking exon 6-7 (e6-7 KO) and KOs lacking exon 7 (e7 KO) by performing RNA-seq. In this study, we expanded transcriptomic analyses to identify novel transcriptional variants in the KO mice. We found prominent expression of a novel exon (exon 4' or e4') between the existing exons 4 and 5 in the Shank2 e6-7 KO model. Expression of the transcriptional variant harboring this novel exon was confirmed by RT-PCR and western blotting. These findings suggest that the novel variant may function as a modifier gene, which contributes to the differences between the two Shank2 mutant lines. Furthermore, our result further represents an example of genetic compensation that may lead to phenotypic heterogeneity among ASD patients with mutations in the same gene.

Local Spectroscopies Reveal Percolative Metal in Disordered Mott Insulators

We elucidate the mechanism by which a Mott insulator transforms into a non-Fermi liquid metal upon increasing disorder at half filling. By correlating maps of the local density of states, the local magnetization, and the local bond conductivity, we find a collapse of the Mott gap toward a V-shaped pseudogapped density of states that occurs concomitantly with the decrease of magnetism around the highly disordered sites but an increase of bond conductivity. These metallic regions percolate to form an emergent non-Fermi liquid phase with a conductivity that increases with temperature. Bond conductivity measured via local microwave impedance combined with charge and spin local spectroscopies are ideal tools to corroborate our predictions.

Radiation dose reduction and improvement of image quality in digital chest radiography by new spatial noise reduction algorithm

Purpose

To evaluate the image quality of low-dose chest digital radiographic images obtained with a new spatial noise reduction algorithm, compared to a conventional de-noising technique.

Materials and methods

In 69 patients, the dose reduction protocol was divided into A, B, and C test groups– 60% (n = 22), 50% (n = 23), and 40% (n = 24) of the baseline dose. In each patient, baseline dose radiographs were obtained with conventional image processing while low-dose images were acquired with new image processing. A set of baseline and low-dose radiographic images per patient was evaluated and scored on a 5-point scale over seven anatomical landmarks (radiolucency of unobscured lung, pulmonary vascularity, trachea, edge of rib, heart border, intervertebral disc space, and pulmonary vessels in the retrocardiac area) and three representative abnormal findings (nodule, consolidation, and interstitial marking) by two thoracic radiologists. A comparison of paired baseline and low-dose images was statistically analyzed using a non-inferiority test based on the paired t-test or the Wilcoxon signed-rank test.

Results

In A, B, and C test groups, the mean dose reduction rate of the baseline radiation dose was 63.4%, 53.9%, and 47.8%, respectively. In all test groups, the upper limit of the 95% confidence interval was less than the non-inferiority margin of 0.5 every seven anatomical landmarks and three representative abnormal findings, which suggested that the image quality of the low-dose image was not inferior to that of the baseline dose image even if the maximum average dose reduction rate was reduced to 47.8% of the baseline dose.

Conclusion

In our study, an image processing technique integrating a new noise reduction algorithm achieved dose reductions of approximately half without compromising image quality for abnormal lung findings and anatomical landmarks seen on chest radiographs. This feature-preserving, noise reduction algorithm adopted in the proposed engine enables a lower radiation dose boundary for the sake of patient’s and radiography technologist’s radiation safety in routine clinical practice, in compliance with regulatory guidelines.

Application of deep learning to the diagnosis of cervical lymph node metastasis from thyroid cancer with CT: external validation and clinical utility for resident training

PURPOSE

This study aimed to validate a deep learning model's diagnostic performance in using computed tomography (CT) to diagnose cervical lymph node metastasis (LNM) from thyroid cancer in a large clinical cohort and to evaluate the model's clinical utility for resident training.

METHODS

The performance of eight deep learning models was validated using 3838 axial CT images from 698 consecutive patients with thyroid cancer who underwent preoperative CT imaging between January and August 2018 (3606 and 232 images from benign and malignant lymph nodes, respectively). Six trainees viewed the same patient images (n = 242), and their diagnostic performance and confidence level (5-point scale) were assessed before and after computer-aided diagnosis (CAD) was included.

RESULTS

The overall area under the receiver operating characteristics (AUROC) of the eight deep learning algorithms was 0.846 (range 0.784-0.884). The best performing model was Xception, with an AUROC of 0.884. The diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of Xception were 82.8%, 80.2%, 83.0%, 83.0%, and 80.2%, respectively. After introducing the CAD system, underperforming trainees received more help from artificial intelligence than the higher performing trainees (p = 0.046), and overall confidence levels significantly increased from 3.90 to 4.30 (p < 0.001).

CONCLUSION

The deep learning-based CAD system used in this study for CT diagnosis of cervical LNM from thyroid cancer was clinically validated with an AUROC of 0.884. This approach may serve as a training tool to help resident physicians to gain confidence in diagnosis.

KEY POINTS

• A deep learning-based CAD system for CT diagnosis of cervical LNM from thyroid cancer was validated using data from a clinical cohort. The AUROC for the eight tested algorithms ranged from 0.784 to 0.884. • Of the eight models, the Xception algorithm was the best performing model for the external validation dataset with 0.884 AUROC. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 82.8%, 80.2%, 83.0%, 83.0%, and 80.2%, respectively. • The CAD system exhibited potential to improve diagnostic specificity and accuracy in underperforming trainees (3 of 6 trainees, 50.0%). This approach may have clinical utility as a training tool to help trainees to gain confidence in diagnoses.

Abstract GS6-06: A neoadjuvant trial with letrozole identifies PRR11 in the 17q23 amplicon as a mechanism of resistance to endocrine therapy in ER-positive breast cancer

Although the 17q23 amplicon has been associated with luminal B breast cancer (BC) and high risk of recurrence, a specific gene or genes in this region that would be causal to endocrine resistance have not yet been uncovered. We performed whole transcriptome analysis on RNA extracted from 58 estrogen receptor (ER)+ BCs treated with neoadjuvant letrozole for median 7.2 months. PRR11 (Proline rich 11), located in 17q23, was upregulated in non-responding tumors as defined by relapse after a median follow up of 5 years and/or a preoperative endocrine prognostic index (PEPI) ≥4. Differential gene expression analysis between tumors expressing low vs high PRR11 mRNA showed that BC signatures associated with proliferation, IGF-1 and PI3K signaling were enriched in tumors with high PRR11 expression.

Rate of PRR11 amplification is 15.2% in the Metastatic Breast Cancer project, but 9.5% and 9.4% in METABRIC and The Cancer Genome Atlas (TCGA), respectively. Gene Set Enrichment Analysis revealed an enrichment of hallmark gene sets associated with proliferation in PRR11-amplified ER+ BCs in METABRIC and TCGA. Integrated analysis of gene expression with on-treatment Ki67 levels from three independent studies with operable ER+ BCs treated with neoadjuvant aromatase inhibitor (ACOSOG-Z1031, NCT00651976, Llombart-Cussac et al.) showed that PRR11 was the only gene in 17q23 with a significant correlation with a high Ki67 levels across all studies.

PRR11 knockdown inhibited E2-independent growth of HCC1428 LTED (long-term estrogen deprived) and MCF7 LTED cells in culture and MCF7 xenografts. PRR11 siRNA also inhibited growth of fulvestrant-resistant and tamoxifen-resistant MCF7 cells. Conversely, PRR11 transduction induced MDA-MB-134VI cell growth under estrogen-depleted conditions. Using a PCR array with 84-cell cycle genes, we identified SKP2, CDKN1A, CCNB2, CCNA2, CKS2 and CCNB1 as genes downregulated by PRR11 knockdown. Except for SKP2 and CDKN1A, expression of all those genes was elevated in PRR11-amplifiedER+ BCs in TCGA and METABRIC.

Suggesting a link to activation of PI3K signaling, we found the proline-rich motif of PRR11 associates with the SH3 domain of the p85 regulatory subunit of PI3K. We hypothesized that this association suppresses p85 homodimer formation, thus facilitating binding of PI3Kα (p110α)-p85 dimers to IRS1, retention of p110α at the plasma membrane and, hence, activation of PI3K/AKT. To test this, we co-transfected HEK293T cells with HA-p85 and FLAG-p85. Forced expression of PRR11 reduced HA-p85 and FLAG-p85 homodimers as shown by HA and FLAG pulldowns followed by FLAG and HA immunoblots, respectively. PRR11 overexpression enhanced insulin-stimulated association of IRS1 to p110α and activation of AKT. PRR11 knockdown reduced insulin/IGF-1/2-stimulated p-AKT. In METABRIC and TCGA, PRR11 amplification and PIK3CA mutations are exclusive of each other, suggesting these alterations would be functionally linked with the same pathway.

Connectivity map analysis with the list of genes significantly overexpressed in ER+/PRR11-amplified BCs predicted PI3K inhibitors as perturbations that suppress such gene list. In the MGH/Sanger dataset, PRR11-amplified BC cell lines displayed significantly higher sensitivity to the pan-PI3K inhibitor pictilisib compared to cell lines without PRR11 amplification. Finally, inhibition of PI3Kα by siRNA or alpelisib abrogated E2-independent growth and insulin-stimulated growth of PRR11-transduced MDA-MB-134VI and MCF10A cells, respectively, suggesting p110α is required for the growth promoting effects of PRR11.

These data suggest that 1) PRR11 is a mediator of resistance to antiestrogens via amplification of PI3K/AKT signaling, and 2) PI3Kα is a potential therapeutic target in ER+ BCs harboring PRR11 amplification.

Citation Format: Kyung-min Lee, Angel Guerrero-Zotano, Ariella Hanker, Alberto Servetto, Dhivya Sudhan, Luigi Formisano, Valerie Jansen, Paula González-Ericsson, Melinda Sanders, Thomas Stricker, Lewis Cantley, Carlos Arteaga. A neoadjuvant trial with letrozole identifies PRR11 in the 17q23 amplicon as a mechanism of resistance to endocrine therapy in ER-positive breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr GS6-06.

Abstract PD7-04: Fibroblast growth factor receptor 1 associates with promoters genome-wide and regulates gene transcription in ER+/FGFR1-amplified breast cancer: Implications for endocrine resistance

Background: FGFR1 amplification occurs in about 15% of estrogen receptor-positive (ER+) breast cancers and is associated with resistance to endocrine therapy. In these tumors, nuclear FGFR1 has been shown to interact with ERα and alter gene expression through binding to chromatin. However, the mechanisms underpinning nuclear FGFR1-mediated gene transcription remain unclear. Thus, we sought to elucidate mechanisms to explain the genomic role of FGFR1 in ER+/FGFR1-amplified breast cancer.Results: FGFR1 ChIP-Seq detected 4408 DNA binding sites in CAMA1 ER+/FGFR1-amplified breast cancer cells cultured in estrogen-free conditions; 67% of these sites were enriched at promoter regions, suggesting a role of FGFR1 in gene transcription regulation. ChIP-qPCR assay confirmed FGFR1 binding to promoter regions of genes such as CCND1, MYC, VEGFA, JUNB and SMAD5 in both CAMA1 and MDA-MB-134 ER+/FGFR1-amplified cells and also in an ER+/FGFR1-amplified patient derived xenograft (HCI-011). RNA-Seq of CAMA1 cells revealed that expression of FGFR1-bound genes was substantially higher than non FGFR1-bound genes (p&lt;0.0001), suggesting FGFR1 binds to genes that are actively transcribed. Consistent with these results, precipitation with a FGFR1 antibody followed by immunoblot analysis showed association of FGFR1 with RNA Polymerase II (Pol II) in CAMA1, MDA-MB-134 and HCI-011 cell extracts. FGFR1 mainly bound with Pol II phosphorylated in Ser5 (Pol II S5P), a post-translational modification required for transcriptional activity. ChIP-Seq in CAMA1 cells with a Pol II S5P antibody revealed that 2867 of 4408 (65%) FGFR1 binding sites overlapped with Pol II S5P peaks, with a distribution centered on a similar location near the transcription start site. This interaction was validated by ChIP-reChIP assay, via sequential immunoprecipitation of FGFR1 and Pol II. Analysis of the METABRIC cohort showed that 1096/4408 (25%) FGFR1 DNA binding sites overlapped with genes differentially expressed in FGFR1-amplified vs FGFR1 non-amplified ER+ breast cancers. From this 1096-overexpressed gene list and using Gene Set Variation Analysis (GSVA), we developed a signature score for the top 102 genes (LogFC&gt;0.25), representing those whose expression is likely regulated by FGFR1. This high signature score was associated with worse disease free survival (DFS; 263.7 months vs not reached; HR=1.72, CI 1.39-2.12; p&lt;0.0001) and overall survival (OS; 145.1 vs 174.1 months; HR=1.24, CI 1.07-1.43; p=0.0003) in the ER+/HER2− cohort in METABRIC. This high signature score also correlated with high tumor grade (p&lt;0.0001) and a worse Nottingham prognostic index (p&lt;0.0001). Finally, we investigated cofactors influencing FGFR1 genomic function. Since nuclear FGFR1 has been shown to interact with ERα, we examined those cofactors involved in ER transcription. We initially focused on the FOXA1 pioneer factor, which mediates transcription factor binding to chromatin in ER+ breast cancer cells. Precipitation with a FGFR1 antibody followed by FOXA1 immunoblot analysis demonstrated an association of FGFR1 with FOXA1 in CAMA1 and MDA-MB-134 cells. ChIP in CAMA1 cells revealed FOXA1 enrichment at promoter regions bound by FGFR1. Further, siRNA-mediated FOXA1 knockdown in CAMA1 cells markedly reduced FGFR1 binding to several promoter regions, preliminarily including CCND1, JUNB, SMAD5, MYC and TOB1, as measured by ChIP-qPCR. Conclusions: These findings suggest a prominent role of FGFR1 in gene transcription regulation in breast cancer. Whether this transcriptional action is causal to antiestrogen resistance in ER+/FGFR1-amplified breast cancer is under active investigation and will be reported at the Symposium.

Citation Format: Alberto Servetto, Rahul Kollipara, Luigi Formisano, Kyung-min Lee, Dhivya R Sudhan, Ariella B Hanker, Sumanta Chatterjee, Albert Lin, Saurabh Mendiratta, Nicholas James, Ralf Kittler, Carlos L Arteaga. Fibroblast growth factor receptor 1 associates with promoters genome-wide and regulates gene transcription in ER+/FGFR1-amplified breast cancer: Implications for endocrine resistance [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr PD7-04.

The application of human pluripotent stem cells to model the neuronal and glial components of neurodevelopmental disorders

Cellular models of neurodevelopmental disorders provide a valuable experimental system to uncover disease mechanisms and novel therapeutic strategies. The ability of induced pluripotent stem cells (iPSCs) to generate diverse brain cell types offers great potential to model several neurodevelopmental disorders. Further patient-derived iPSCs have the unique genetic and molecular signature of the affected individuals, which allows researchers to address limitations of transgenic behavioural models, as well as generate hypothesis-driven models to study disorder-relevant phenotypes at a cellular level. In this article, we review the extant literature that has used iPSC-based modelling to understand the neuronal and glial contributions to neurodevelopmental disorders including autism spectrum disorder (ASD), Rett syndrome, bipolar disorder (BP), and schizophrenia. For instance, several molecular candidates have been shown to influence cellular phenotypes in three-dimensional iPSC-based models of ASD patients. Delays in differentiation of astrocytes and morphological changes of neurons are associated with Rett syndrome. In the case of bipolar disorders and schizophrenia, patient-derived models helped to identify cellular phenotypes associated with neuronal deficits (e.g., excitability) and mutation-specific abnormalities in oligodendrocytes (e.g., CSPG4). Further we provide a critical review of the current limitations of this field and provide methodological suggestions to enhance future modelling efforts of neurodevelopmental disorders. Future developments in experimental design and methodology of disease modelling represent an exciting new avenue relevant to neurodevelopmental disorders.

Cell-specific expression of Epac2 in the subventricular and subgranular zones

Aim

cAMP signal transduction cascade activation is important in regulating neurogenesis in adult rodents by increasing the proliferation of newborn cells. Although the ventricular-subventricular zone (V-SVZ) and subgranular zone (SGZ) both contain large populations of neural stem/precursor cells; it remains unclear whether an alternative target of cAMP, the exchange protein directly activated by cAMP (Epac2), is involved in adult neurogenesis in the V-SVZ and SGZ. Here, we investigated the cell-specific expression of Epac2 protein in the V-SVZ and SGZ of the adult mouse brain.

Methods

Immunohistochemical analyses were performed using antibodies against Epac2, glial fibrillary acidic protein (GFAP), doublecortin (DCX), and beta-catenin, to examine the co-localization of Epac2 protein and neural stem/precursor cells in the V-SVZ and SGZ in three 8-week-old male mice.

Results

In the V-SVZ of the lateral ventricle, most GFAP-positive adult neural stem cells (NSC, defined as type B cells) and 75% of DCX-positive migrating neuroblasts (type A cells) expressed Epac2 proteins. Ninety-three percent of beta-catenin-positive ependymal cells (type E cells), which are in direct contact with NSCs and the ventricles, also expressed Epac2 protein. Similarly, in the SGZ of the hippocampus, Epac2-immunopositive signals were shown by 83% of GFAP-positive radial-glia-like NSCs (type 1 cells), 86% of DCX-positive transiently amplifying cells (type 2 and type 3 cells), and 71% of DCX-positive immature neurons. The present data suggest that a PKA-independent cAMP signaling pathway via Epac2 may be party to adult neurogenesis in the V-SVZ and the SGZ.

Efficacy of a povidone-iodine foam dressing (Betafoam) on diabetic foot ulcer

This study aimed to assess the efficacy of a new povidone-iodine (PVP-I) foam dressing (Betafoam) vs foam dressing (Medifoam) for the management of diabetic foot ulcers. This study was conducted between March 2016 and September 2017 at 10 sites in Korea. A total of 71 patients (aged ≥19 years) with type 1/2 diabetes and early-phase diabetic foot ulcers (Wagener classification grade 1/2) were randomised to treatment with PVP-I foam dressing or foam dressing for 8 weeks. Wound healing, wound infection, patient satisfaction, and adverse events (AEs) were assessed. The PVP-I foam and foam dressing groups were comparable in the proportion of patients with complete wound healing within 8 weeks (44.4% vs 42.3%, P = .9191), mean (±SD) number of days to complete healing (31.00 ± 15.07 vs 33.27 ± 12.60 days; P = .6541), and infection rates (11.1% vs 11.4%; P = 1.0000). Median satisfaction score (scored from 0 to 10) at the final visit was also comparable between groups (10 vs 9, P = .2889). There was no significant difference in AE incidence (27.8% vs 17.1%, P = .2836), and none of the reported AEs had a causal relationship with the dressings. The results of this study suggest that PVP-I foam dressing has wound-healing efficacy comparable with foam dressing, with no notable safety concerns. This study was funded by Mundipharma Korea Ltd and registered at ClinicalTrials.gov (identifier NCT02732886).

P4791Performance of the HAS-BLED, ATRIA, and PRECISE-DAPT Bleeding Risk Scores in Atrial Fibrillation Patients Using Antiplatelet Agents or Oral Anticoagulants

Background

Various bleeding risk scores have been proposed to assess the risk of bleeding in atrial fibrillation (AF) patients undergoing anticoagulation. PRECISE DAPT score has been developed to assess the out-of hospital bleeding risk in patients receiving dual antiplatelet therapy (DAPT). Our objective was to compare the predictive performance between the HAS-BLED (Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile International Normalized Ratio, Elderly, Drugs/Alcohol), ATRIA (Anticoagulation and Risk Factors in Atrial Fibrillation), and PRECISE-DAPT (Predicting Bleeding Complication in Patients Undergoing Stent Implantation and Subsequent Dual Antiplatelet therapy) score in AF patients using antiplatelet agents or anticoagulants

Methods

We recruited 1,114 consecutive AF patients (51% male; median age, 71 years) receiving antiplatelet agents or oral anticoagulants from January 2014 through December 2018. Major bleeding was defined as according to the Bleeding Academic Research Consortium (BARC) criteria (type 3 or 5: hemodynamic instability, need for transfusion, drop in hemoglobin ≥3 g, and intracranial, intraocular or fatal bleeding). The performance of risk scores were assessed by C-statistic.

Results

Bleeding events occurred in 135 patients (12.1%) during 30 days, and 72 patients (6.5%) from 30 days till 1-year follow-up. Based on the C-statistic, PRECISE-DAPT score (AUC: 0.72, 95% CI: 0.69–0.75) had a good performance, significantly better than HAS-BLED (AUC: 0.64, 95% CI: 0.61–0.67) (p=0.008) or ATRIA scores (AUC: 0.57, 95% CI: 0.54–0.60) (p<0.001) for 30-days bleeding prediction. Also, PRECISE-DAPT score had a good C-statistic (AUC: 0.72, 95% CI: 0.69–0.75) for 1-year bleeding events compared with HAS-BLED (AUC: 0.64, 95% CI: 0.60–0.67) (p=0.02) or ATRIA (AUC: 0.61, 95% CI: 0.58–0.65) (p=0.01).

ROC curve for bleeding

Conclusions

The PRECISE-DAPT score has been used for assessing bleeding events during DAPT. Also, the PRECISE-DAPT score predicted bleedings better than HAS-BLED or ATRIA scores in AF patients. So, the PRECISE-DAPT score may be considered as bleeding risk score during DAPT or oral anticoagulation in clinical practice.

P4776Age-dependent anti-thrombotic therapy for atrial fibrillation patients with intermediate risk (CHA2DS2-VASc Score of 1 or 2) of ischemic stroke

Background

Although older age is one of the most important risk factor for stroke in atrial fibrillation (AF), it is unclear whether oral anticoagulants are beneficial for AF patients with intermediate CHA2DS2-VASc score (1 for male or 2 for female) according to age threshold. We sought to investigate the effect of age-dependent antithrombotic therapy for ischemic stroke in Korean intermediate risk AF patients.

Methods

We enrolled 29,592 patients (males with CHA2DS2-VASc score of 1 and females with CHA2DS2-VASc score of 2) using the Korean National Health Insurance Service database. The clinical endpoint was the occurrence of ischemic stroke. The propensity score matching method was used to balance covariates across treated and untreated patients.

Results

Treated male AF patients were 6,570 (67.1%) with age <55 years, 7,115 (70.9%) with 55–64 years and 6,470 (68.3%) with 65–74 years in each age risk criterion. Also, treated female AF patients were 3,156 (71.3%) with age <55 years, 2,838 (71.0%) with 55–64 years and 3,440 (72.6%) with 65–74 years in each age risk criterion. Among male and female patients (age <55 years and 55–64 years) with 1 risk factor, an annual ischemic stroke rate was not significantly different between treated and untreated patients at full follow-up. However, treated AF patients who are in age 65–74 year without other risk factor had a much lower annual risk of ischemic stroke [(1.05%/year (male) and 1.04%/year (female)] compared with untreated patients [(1.77%/year (male) (p<0.026) and 1.86%/year (female) (p<0.041).

Conclusions

Age is an important predictor in determining the risk of ischemic stroke in AF patients with intermediate CHA2DS2-VASc scores (1 for male or 2 for female). We suggest that the benefit of anti-thrombotic therapy for intermediate risk AF patients depends on age threshold.

P5661Validation of CHA2DS2-VA score (excluding female sex) in non-valvular atrial fibrillation patients: a nationwide population-based study

Background

Sex category (Sc, ie, female sex) confers 1 point on CHA2DS2-VASc score. So, no woman with atrial fibrillation (AF) can have a CHA2DS2-VASc score of 0. This study aimed to compare CHA2DS2-VA (excluding female sex) and CHA2DS2-VASc score in Korean AF patients.

Methods

Using the Korean National Health Insurance Service database, we analyzed the risk of ischemic stroke in non-valvular AF patients between 2013 and 2017. The predictive value of the CHA2DS2-VA and CHA2DS2-VASc scores for ischemic stroke was evaluated by c-statistic difference and net reclassification improvement (NRI). The propensity score matching method was used to balance covariates across male and female AF patients.

Results

A total of 182,133 patients with AF (49.2% women) were included to this study. The adjusted incidence rate (IR) of ischemic stroke was not significantly different between males and females (0.89%/y and 0.90%/y, respectively, p=0.411) in low-risk patients without risk factor. Also, no sex difference was found in high-risk patients with above 2 risk factors for ischemic stroke (4.46%/y for male and 4.49%/y for male, p=0.498). In c-statistic analysis for ischemic stroke, there was no significant difference between the CHA2DS2-VA and CHA2DS2-VASc scores (AUC 0.662 vs. 0.664, z=1.572, p=0.116). When compared with CHA2DS2-VASc score, CHA2DS2-VA score was not significantly inferior in net reclassification improvement (NRI 0.031, 95% CI 0.002–0.037, p=0.118) for ischemic stroke.

C-statistics

Conclusions

In Korean AF patients, the CHA2DS2-VA score excluding female sex is a useful risk scoring system for ischemic stroke.

A reliable approach for assessing size-dependent effects of silica nanoparticles on cellular internalization behavior and cytotoxic mechanisms

Background

The size of nanoparticles is considered to influence their toxicity, as smaller-sized nanoparticles should more easily penetrate the cell and exert toxic effects. However, conflicting results and unstandardized methodology have resulted in controversy of these size-dependent effects. Here, we introduce a unique approach to study such size-dependent effects of nanoparticles and present evidence that reliably supports this general assumption along with elucidation of the underlying cytotoxic mechanism.

Methods

We prepared and physically characterized size-controlled (20-50 nm) monodispersed silica nanoparticles (SNPs) in aqueous suspensions. Then, a variety of biochemical assessments are used for evaluating the cytotoxic mechanisms.

Results

SNP treatment in three cell lines decreased cell viability and migration ability, while ROS production increased in dose- and size-dependent manners, with SNPs <30 nm showing the greatest effects. 30- and 40-nm SNPs were observed similar to these biological activities of 20- and 50-nm, respectively. Under the conventionally used serum-free conditions, both 20-nm and 50-nm SNPs at the IC₅₀ values (75.2 and 175.2 μg/mL) induced apoptosis and necrosis in HepG2 cells, whereas necrosis was more rapid with the smaller SNPs. Inhibiting endocytosis impeded the internalization of the 50-nm but not the 20-nm SNPs. However, agglomeration following serum exposure increased the size of the 20-nm SNPs to approximately 50 nm, preventing their internalization and cell membrane damage without necrosis. Thus, 20-nm and 50-nm SNPs show different modes of cellular uptake, with smaller SNPs capable of trafficking into the cells in an endocytosis-independent manner. This approach of using non-overlapping size classes of SNPs under the same dose, along with serum-induced agglomeration analysis clarifies this long-standing question about the safety of small SNPs.

Conclusion

Our results highlight the need to revise safety guidelines to account for this demonstrated size-dependent cytotoxicity under serum-free conditions, which may be similar to the microenvironment after tissue penetration.

Spatial Learning and Motor Deficits in Vacuolar Protein Sorting-associated Protein 13b (Vps13b) Mutant Mouse

Vacuolar protein sorting-associated protein 13B (VPS13B), also known as COH1, is one of the VPS13 family members which is involved in transmembrane transport, Golgi integrity, and neuritogenesis. Mutations in the VPS13B gene are associated with Cohen syndrome and other cognitive disorders such as intellectual disabilities and autism spectrum disorder (ASD). However, the patho-physiology of VPS13B-associated cognitive deficits is unclear, in part, due to the lack of animal models. Here, we generated a Vps13b exon 2 deletion mutant mouse and analyzed the behavioral phenotypes. We found that Vps13b mutant mice showed reduced activity in open field test and significantly shorter latency to fall in the rotarod test, suggesting that the mutants have motor deficits. In addition, we found that Vps13b mutant mice showed deficits in spatial learning in the hidden platform version of the Morris water maze. The Vps13b mutant mice were normal in other behaviors such as anxiety-like behaviors, working memory and social behaviors. Our results suggest that Vps13b mutant mice may recapitulate key clinical symptoms in Cohen syndrome such as intellectual disability and hypotonia. Vps13b mutant mice may serve as a useful model to investigate the pathophysiology of VPS13B-associated disorders.

Abstract 4402: FGFR1 signaling modulates estrogen-independent ER transcriptional activity in ER+/FGFR1-amplified breast cancer cells

Background: FGFR1 amplification occurs in about 15% of estrogen receptor-positive (ER+) breast cancers and is associated with resistance to endocrine therapy. In these tumors, nuclear FGFR1 has been shown to interact with ERα. In addition, FGFR1 has been demonstrated to alter gene expression through binding to chromatin. However, the mechanisms underpinning nuclear FGFR1-mediated gene transcription remain unclear. Thus, we sought to elucidate the genomic and non-genomic role of FGFR1 in ER+/FGFR1-amplified breast cancer.

Methods: FGFR1 ChIP-Seq and ERα ChIP-Seq were performed on CAMA1 ER+/FGFR1-amplified breast cancer cells. ChIP-qPCR was employed to quantify DNA binding events. For ChIP-Seq, immunoblot, RT-qPCR, Estrogen Response Element (ERE) luciferase reporter and growth assays, CAMA1 cells were plated in estrogen-free media for 24 hours and then stimulated with 100 ng/ml FGF3 or 1 nM β-Estradiol.

Results: FGFR1 ChIP-Seq detected 2211 DNA binding sites in CAMA1 cells cultured in estrogen-free conditions. Gene Set Enrichment Analysis (GSEA) revealed that the TNFα signaling via NF-KB, MYC targets, G2M checkpoints, ERE early and ERE late response genes (all FDR &lt;0.00001) were among the most enriched gene sets. The majority of binding sites occurred in promoter regions, supporting a role of FGFR1 in regulation of gene transcription. FGFR1 ChIP-qPCR confirmed FGFR1 binding to promoter regions of oncogenes including CCND1, MYC, VEGFA, JUNB and SMAD5. FGF3 stimulation of CAMA1 cells further enriched FGFR1 binding to the CCND1 promoter and upregulation of CCND1 mRNA and protein levels. These effects were ablated upon addition of the pan-FGFR tyrosine kinase inhibitor rogaratinib. Motif analysis revealed CTCF (CCCTC binding factor) as the most enriched motif (p=1e-91). siRNA-mediated knockdown of CTCF inhibited FGF3-induced ERα transcriptional activity and proliferation of CAMA1 cells. These results suggest a role for CTCF in mediating the transcriptional programs regulated by FGFR1. We reported an association of nuclear FGFR1 and ERα in ER+/FGFR1-amplified breast cancer cells. Thus, we next investigated the role of FGF3-induced FGFR signaling on estrogen-independent ERα transcription using ERα ChIP-Seq. FGF3 stimulation of CAMA1 cells resulted in 407 DNA binding sites of which 155 were unique compared to cells in the absence of ligand. GSEA of these 155 peaks revealed enrichment for ERE early (p=3.08e-17) and ERE late (p=2.6e-5) response genes. FGF3-mediated induction of ERα transcriptional program was confirmed by ERE reporter assay and was abrogated by treatment with rogaratinib.

Conclusions: These findings suggest a FGFR1 kinase-dependent role on ER-mediated transcription in ER+/FGFR1-amplified breast cancer cells. We are currently performing mass spectrometry analysis to identify binding partners of nuclear FGFR1 that mediate its transcriptional function.

Citation Format: Alberto Servetto, Luigi Formisano, Rahul Kollipara, Dhivya R. Sudhan, Kyung-min Lee, Sumanta Chatterjee, Ariella B. Hanker, Saurabh Mendiratta, Ralf Kittler, Carlos L. Arteaga. FGFR1 signaling modulates estrogen-independent ER transcriptional activity in ER+/FGFR1-amplified breast cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4402.

Spectrally tunable chiral Bragg reflectors for on-demand beam generation

We demonstrate the generation of spectrally tunable phase-dependent wavefronts, using the 2D Airy as the primary test case, via a polymer-stabilized cholesteric liquid crystal (PSCLC) element. Specifically, we use a novel spatial light modulator (SLM) based projection system to photo-align the initial helix angle landscape of the PSCLC so that it imparts the appropriate cubic phase profile to the reflected beam. This element is spectrally selective, with a reflection bandwidth of ≈ 100 nm, and electrically tunable from λ = 530 nm to 760 nm. Under both green and red laser illumination, the element is shown to conditionally form an Airy beam depending on the position of the electrically tailored reflection band. We briefly demonstrate the generality of this approach by producing PSCLC elements which form a computer-generated hologram and a higher-order Mathieu beam.

A systemic lupus erythematosus patient with thunderclap headache: reversible cerebral vasoconstriction syndrome

Headaches are common in patients with systemic lupus erythematosus (SLE). It is important to identify the exact cause of headaches in SLE to avoid unnecessary steroid or immunosuppressive therapy like in neuropsychiatric SLE. A 35-year-old woman with SLE suddenly developed severe headache. Magnetic resonance angiography showed multifocal segmental narrowing of cerebral arteries, suggestive of central nervous system vasculitis. However, lack of abnormal enhancement in vessel wall imaging indicated reversible cerebral vasoconstriction syndrome (RCVS) rather than central nervous system vasculitis. The patient was treated with oral nimodipine and she recovered over a period of two months. Following magnetic resonance angiography on day 90 was normal. Herein we report a case of reversible cerebral vasoconstriction syndrome in an SLE patient with literature review.